When you hear the term fasting, you might immediately think of a religious practice, but quite recently fasting has become the latest trend in the world of weight loss. So what exactly happens if you don’t eat for a day? The answer might sound simple, but fasting for 24 hours has a complex ripple effect within the body.
Defined as the abstinence from all or some foods or drinks for a set period of time, there are many different ways of fasting. A form of fasting known as ‘intermittent fasting’ is gaining popularity as a weight loss tool. Intermittent fasting involves cycling between periods of eating and fasting, ranging from a few hours to a few days at a time.
The benefits of fasting are astounding. Fasting is one of the most powerful tools on the planet for stubborn weight loss, reversing insulin resistance, and protecting the body against heart disease, liver disease and even cancer. Did you know fasting also helps our immune systems get stronger, increases our metabolism, and helps increase the secretion of growth hormones, making us more energetic and more youthful?
What happens during fasting?
The body continuously demands energy. Its primary energy source is a form of sugar called glucose, which we usually get from carbohydrates like drinks, grains, dairy products, fruits, certain vegetables, and sweets. Our muscles and liver store glucose and release it into the bloodstream whenever the body needs it.
When a person is fasting however this process changes. During the first 8 hours, your body will continue to digest its last intake of food. During fasting, the liver uses the last glucose reserve for energy. At this point, the body enters into a state called gluconeogenesis, marking the body’s transition into fasting mode. Studies have shown that gluconeogenesis increases the number of calories the body burns.
With no carbohydrates coming in, the body creates its glucose mainly using fat. Eventually, the body runs out of these energy sources (fat) as well. Fasting mode then becomes a more severe starvation mode. Your body will continue to use stored fat to create energy throughout the remainder of this 24-hour fast. If the fast lasts longer than 24 hours, your body starts converting stored protein into energy. When the starvation mode is reached, a person’s metabolism slows down, and the body begins burning muscle tissue for energy. But in dieting culture, the real starvation mode only occurs after several consecutive days or even weeks without food.
Can fasting promote weight loss?
It does appear that fasting can help with weight loss. However, studies have proved that it might not be helpful for everyone. Popular diet plans include 6-hour, 12-hour or 24-hour fasting periods. Some diets require people to drink any zero-calorie beverage while others only allow water during fasting. In a recent study, people with obesity who were intermittently fasting for 12 months lost slightly more weight than those who were dieting in a more traditional way.
The limits of fasting appear to have less to do with its physical effects than how it fits into a given lifestyle. Researchers have concluded that fasting might be harder to maintain over time, but it might work for short time programs. Some fasting experts agree that it’s easy to override weight-loss benefits by overeating after the fasting period.
When we function in a sugar burning mode, we do not fully use up our stored sugar before we eat the next meal. As a result, the sugar is always burnt and the stage where the fat is burnt is never really reached. Sugar, in the form of glycogen, is stored in the liver and muscles. This ‘easy’ energy is consumed in our body only when the body starts accessing the fat stores and begins using it for energy. So when the fat starts burning your body can lose weight by using up fat stores (that are usually unwanted) on the body.
Drinking enough water is essential for your everyday health, whether you’re eating or fasting. The body requires plenty of water, even more than eight glasses during a 24-hour fast. Water helps the digestive system, regulates the body temperature, benefits joints and tissues, and keeps you feeling energized throughout the day.
Many health advisories recommend drinking eight 8-ounce glasses (about 2 liters) of water every day. Ultimately, your thirst should be your guide when it comes to water intake as it’s different for each individual.
Risks of fasting
Although fasting is generally considered safe but going a day without eating can be risky for some people, for example:
- people with type 1 diabetes
- people with a history of eating disorders
- people recovering from surgery
- women who are pregnant or breastfeeding
- children and adolescents under the age of 18
What is the safest way to break a fast?
According to Chelsey Amer, a registered dietitian nutritionist, there are several ways to break your fast effectively and more importantly, safely:
- Drink water: This is especially important if circumstances prevented it during the fast.
- Eat a small meal: Eating a large meal immediately after a fast can strain the digestive system.
- Eat cooked foods: Opt for foods that are easier to digest, like cooked vegetables instead of raw ones.
- Chew food thoroughly: Chew each bite at least 30 times.
- Avoid experimenting: Trying new foods after a fast can make digestion harder and may make a person feel sick.
Fasting has value
Going a day without eating is generally safe and can be super beneficial. When you fast as a weight loss method, the idea is not to consume more than 1200 calories; which even if you kind of surpass by accident you still lose weight because you’re on a deficit given that you’re fasting. In other words, you’re basically just following a simple calorie deficit diet.
Fasting programs are easier to maintain than traditional, calorie-controlled diets and easy to follow. If you’re fasting for health reasons, it is essential that you do it safely and for no longer than is actually necessary. Long-term fasting however starves the body of essential nutrients and can end up causing many complications.